/Engine/Source/Runtime/Engine/Classes/Materials/MaterialExpressionRuntimeVirtualTextureSampleParameter.h
If this is the named parameter from this material expression, then set its value.
bool SetParameterValue ( [FName](API\Runtime\Core\UObject\FName) InParameterName, [URuntimeVirtualTexture](API\Runtime\Engine\VT\URuntimeVirtualTexture) * InValue, EMaterialExpressionSetParameterValueFlags Flags )